Effects of Different Photoperiodic Regimes on the Body Mass, Behavioural and Stress Responses in Golden Mahseer, Tor putitora

Golden mahseer, Tor putitora is a teleostean cold-water fish, known to occur in the rivers of Himalayas. Light affects physiology fish. Therefore, study was carried out evaluate effects different photoperiodic regimes as environmental cues on development body mass, behavioural and stress responses T. . Fishes were exposed such 8 hours light: 16 dark (8L:16D), light (16L:8D) natural condition. The cortisol profiling studied. Ethovision (XT-13) used record fish after exposure various regimes. difference scoring recorded groups juveniles Effects skeletons condition (Control) exhibited remarkable differences biomass enhancement (P<0.05). Maximum amount (0.93± 0.08ng/ml) group 16L:8D compared (0.78± 0.21ng/ml) 8L:16D regime (0.69± 0.11ng/ml). A significant (P<0.05) green, red colour noticed, where velocity/swimming speed most affected by green spectra.